There are devices already available to lift a person with the help of lifting equipment that use a one piece sheet with straps, and that are sometimes provided with handles, and which are usually used in combination with a body lifting hoist. Those single piece stretchers are generally used in hospital facilities to lift a standard size person a few feet above ground, either to transfer the person from a bed to a bathtub or a chair. Those sheets have a limited lifting capacity and duty cycle. They are not designed to tolerate human body fluids resulting from paramedical operations, and they generally need to be washed and therefore get worn out by bleaching agents, hence loosing their mechanical strength. They have a relatively low safety factor, usually around 2.5 times their rated loading capacity. They are vulnerable to tear, are unsafe and uncomfortable for an oversize person. See for example those shown in Canadian Patent no. 2,262,067 and in Canadian Patent application no. 2,232,406.
Other apparatuses are also available such as shell stretchers, splints and baskets used for emergency care which are generally made of rigid components that aren't adaptable and require a manual lifting of the body so that it can be laid down on the rigid component. Once installed on the rigid component, the body can be moved or lifted several feet above ground manually or with the help of a mechanical lifting device such as a hoist. Those devices may be equipped with belts or straps to stabilise the body and prevent it from falling. Those devices aren't designed for large size heavy weight persons whom cannot be lifted manually and laid down on the transfer component. When the body is rolled over on this type of device, the frame of the device or its mechanism will usually get in the way and may hurt the person.
The main problem with body transfer devices currently available is that they aren't designed for large size heavy weight persons.
Attempts have been made to find solutions for these problems. For example, U.S. Pat. No. 5,978,989 describes a paramedical stretcher destined to transport corpulent persons. However, the person is not attached to the stretcher and only his or her feet may be placed in a foot pocket.
The use of those existing devices can be unsafe not only for the person who needs to be moved but also for the paramedics staff. Therefore, whereas the existing devices aren't fully suitable, there is a need on the market for a safer and better designed paramedical transfer device for large size heavy weight persons.